[Keyboard] Add VIA support for CA66 (#11522)

* Add VIA support

made changes to add VIA support for the CA66

- added VIA keymap.c, readme.md, rules.mk
- changes made to main rules.mk to keep firmware size down (mousekey_enable = no; backlight_enable = no)
- changed VENDOR_ID in config.h from 0xFEED to 0x504B (PK)

* Minor changes to CA66 for VIA support

edited keymap info
enabled backlight

* Update vendorID

Change to vendorID to remove conflict with previously chosen vendorID already in use

* Update keyboards/playkbtw/ca66/rules.mk

Co-authored-by: Joel Challis <git@zvecr.com>

* Update keyboards/playkbtw/ca66/keymaps/via/readme.md

Co-authored-by: Joel Challis <git@zvecr.com>

* Update keyboards/playkbtw/ca66/keymaps/via/keymap.c

Co-authored-by: Joel Challis <git@zvecr.com>

Co-authored-by: Joel Challis <git@zvecr.com>

keyboards/playkbtw/ca66/config.h

@@ -3,7 +3,7 @@
 #include "config_common.h"
 
 /* USB Device descriptor parameter */
-#define VENDOR_ID       0xFEED
+#define VENDOR_ID       0x5457  // "TW"
 #define PRODUCT_ID      0x6060
 #define DEVICE_VER      0x0001
 #define MANUFACTURER    Barry